Manx Shearwater

Status Uncommon summer visitant. Occurs regularly in small numbers on the Scotian Shelf and in the Bay of Fundy. The earliest spring report is of a bird seen on Browns Bank on 22 April 1976 (J.M. Laughlin); the latest fall sighting was off Sable Island on 1 October 1984.

It would be unusual to sail out of Halifax in July or August without seeing at least one Manx Shearwater. In July 1978 it was the most common shearwater off Sable Island on calm days; no fewer than 125 birds were seen there on 24 July, and it occurred regularly up to 28 August. Numbers have increased significantly since 1970, when the species was placed on the provincial list on the basis of only one specimen and two sight records. The specimen, picked up on the beach at Sable Island on 23 June 1970 by A.R. Lock, had been banded the previous summer at a colony in Wales.

Manx Shearwaters have colonized eastern North America since then; a single nest was discovered in Massachusetts in 1973 (Bierregaard et al. 1975), and a small but expanding colony was established in southern Newfoundland by Welsh birds in 1976 (Storey and Lien 1985). The species nests in burrows and visits its colonies at night only, so it is likely that other breeding sites remain undiscovered. The discovery of Manx Shearwaters breeding in Nova Scotia is probably only a matter of time.

Description Length 31-38 cm. All plumages: The form usually seen off Nova Scotia is dark brown (black at a distance) above, with sharply contrasting white underparts.

Range The subspecies Puffinus puffinus puffinus nests on islands in the eastern North Atlantic from southwest Iceland to the Azores, in southern Newfoundland and, formerly, in Bermuda. The majority of the population breeds in the British Isles. Other subspecies are found in the Mediterranean and the Pacific.

Remarks This species is readily recognized as a medium-small shearwater with long, thin wings and a fast wing-beat interspersed with glides. The Sable Island specimen and almost all the birds seen off Nova Scotia have the crisply contrasting black-and white plumage of the subspecies P. p. puffinus. However, single birds seen off Brier Island on 1 September 1978 and on the northeast tip of Georges Bank on 25 June 1980 had markedly brownish underparts (R.G.B. Brown) and possibly belonged to the eastern Mediterranean subspecies Puffinus puffinus yelkouan.